Process for the manufacture of 1-chloro-ethylbenzenes



3Q styrene is very Patented A r. 23,1935

PATE OFFICE PROCESS FOR.

THE MANUFACTURE i-cnLoao-n'rnrmnnznnns OF I Hans Flnlrelstein and Willi Krey, Uerdlngen, Germany, a'ssignors to I. G. Farbenlndustrle Aktlengesellschaft, Irankforhon-the-Main.

' No, Application November 18, '1982.

Serial No. 643,299. 1931 The present invention relates to the manufacture of l-chloro-ethylbenzene, substituted 1- chloro-ethylbenzenes or homologues of l-chloroethy lbenzene from styrene, substituted styrenes or, homologues of styrene. and gaseous hydrogen chloride'bycausing gaseous hydrogen chloride to act on styrene,,substituted styrenes or homo-- logues of styrene or solutions of the same in indiflerent' solvents in the presence of catalytic-ally 1o acting quantities of substances, forming with hydrogen chloride loose addition compounds, that is to say addition compounds, which again readily split up int'othe .components thereof.

1 f The formation of l-chloro-ethylbenzeneby the addition of hydrogen chloride to styrene in accordance with the equation: I a

CeHS-CH=CH2+HC1- CsHe CHC1 CH3 -iskn0wn. I 1., By passing gaseous drogen'chloride into styrene or solutions of styrene in indiflferent solvents the said addition proceeds but slowly.

An increase of the reaction velocity does not take .place on heating, since the solubility'of hydrogen chloride in styrene or in hydrocarbon mixtures containing styrene decreases greatly with increasing temperature.. I In accordance with, he present invention the reaction velocity of greatly increased by the addition capable of forming loose addition hydrogen chloride, which again of substances,

compounds with readily split into the components thereof. The

substances to be employed need be present only 35 inrelati'vely small,-catalytically'acting quantities, for example, in an amount of 0.1.-15% of the styrene. V

Substances of various classes can be employed as catalysts, insofar as they satisfy the stipu- 0 lated conditions, for exainple, alcohols, such as methyl alcohol; ethyl alcohol, propyl alcohol, butyl alcohol, phenyl ethyl acohol, phenyl propyl alcohol-or mixtures of these alcohols, ketones, "such as acetone, ethyl methyl ketone, .diethyl 45 ketone, ethyl propyl ketone, as well asaliphatic H and aromatic amines, such as trimethyl amine, triethyl amine, dibutyl amine, aniline, methyl aniline, dimethyl aniline, diethyl: aniline, 'dimethyl toluidine, furthermore pyridine, picoline, 50 chinoline and also ethers, such as diethyl ether,

* dipropyl ether, propyl 'butyl ether etc.; These action mixture.

hydrogen chloride and In Germany November 24,

[15 Claims. (01. 260-460).

.care is taken to procure the finest state of division, for example, by agitating and especially by addition of an emulsifying agent, for example, by the addition of the sulfonic acids. of alkylated naphthalenes.

In addition to styrene the process is applicable to substituted styrenes, such as halogenated styrenes, for example, the isomeric chloro styrenes and bromo styrenes, furthermore homologues of styrene, for example, the alkylated styrenes, such as the isomeric methyl styrenes, ethyl styrenes and propyl styrenes etc.

The temperature during the reaction may vary according to the conditions. We have obtained good results with temperatures above 0, more particularly with temperatures ranging from about 5 to about 50 C. At temperatures of employ a reflux condenser or to work in a closed vessel under elevated pressure in order to prevent the volatilization of components of the reis applicable with particular advantage to'mixtures or solutions in which in addition to the styrene, substituted styrenes or homologues of styrene other substances are present, for example, aromatic hydrocarbons not containing unsaturated side chains, such as benzene, toluene, xylene etc.', and consequently the process of the present invention may serve to separate the styrene from such mixtures. Raw materials of this kind are for example the fractions boiling between 140-160 of crude benzene (solvent naphtha) obtainable from coal tar or from coal gas or the so-called drip oil, which separates from water gas, carburetted by means of oil, gas, wherein styrene and possibly homologues of styrene are present.

The process The process is further illustrated by the fol- Example -1 A solution of 97 parts by weight of styrene in 903 parts by weight of. the technical mixture of isomeric xylenes is mixed with 5 parts by weight of dimethylaniline. Hydrogen chloride'is introduced into this mixture at room temperature until the increase in weight amounts to about -above 40-50 C. it is in some cases advisable to r 50 parts which requires about 16 hours. Thedimethylaniline, which first separates as the hydrochloride in the form of a fine turbidity, soon.

. redissolves as the poly hydrochloride. The temperature rises somewhat during the introduction acid, which separates in a fine state of division,

hydrogen chloride to react on a material selected Example 2' The dimethylaniline specified in Example 1 is replaced by the same'quantity of methyl alcohol or butylalcohol and the process is carried out as there described: When methyl alcohol has been added stirring must be resorted to to ensure that the methyl alcoholic hydrochloric remains in suspension in the hydrocarbon mixture. When employing butyl alcohol this does not appear to be necessary. The before mentioned quantity of l-chloro-ethylbenzene is obtained by fractional distillationfrom the reaction product. The duration of the reaction amounts to about 16-18 hours.

The reaction velocity may be increased by employing larger quantities of the catalytically acting substance. Thus it is possible to obtain the same result already in 10 to 12 hours in the example described abovejif instead of 5 parts of methyl alcohol 10 parts of methyl alcohol are employed.

Example 3 ture at room temperature for about 14 hours.

The temperature rises somewhat during the introduction of the hydrogen chloride. The crude reaction product is freed from the excess hy-- drochloric acid by washing with a small quantity.

of water and is-then fractionated in vacuo.

.After distilling over the unchanged xylene 98 parts by weight of pure l-chloro-ethylbenzene are obtained, that are about of the amount calculated. In the absence of water only 50% p of the amount calculated are obtained.

Example 4 A solution of parts by weight of styrene (chlorinated in the, nucleus) in 850 parts by weight of benzene is mixed with 5 g. acetone.

Hydrogen chloride is introduced into this mixture at room temperature for about 12 hours.

The crude reaction product is freed from acetone. and excess hydrochloric acid by washing with a small quantity of water. parts by weight of l-chloro-ethylchlorobenzene are obtained by fractional distillation from the. re-' action product.

In the. following claims the term l-ch-loroethylbenzenes is to denote l-chloro-ethylbenzene, halogenated l-chloro-ethylbenrenes and homologues of l-chloro-ethylbenzene:

We claim: j z

1. The process for the manufacture of l-chlorofrom the group consisting of styrene, halogenated styrenes and homologues of styrene in the presence of catalytically acting quantities of substances, forming with hydrogen chloride addition compounds which can be readily split up again.

2. The process for the manufacture of l-chloroethylbenzene, which comprises causing gaseous hydrogen chloride to react on styrene in the pres- 6 ence of catalytically" acting quantities of sub-- stances, forming with hydrogen chloride addition compounds which can be readily split up again.

3. Theprocess for the manufacture of l-chloroethylbenzene, which comprises causing-gaseous l0 hydrogen chloride to react'on a solution of styrene in an inert organic solvent in the presence of catalytically acting quantities of substances, f orm'- ing with hydrogen chloride addition compounds which can be readily split up again. 4. The process for the manufacture of l-chloroethylbenzene, which comprises causing gaseous hydrogen chloride to react on a hydrocarbon fraction containing styrene in the presence of catalytically acting quantities of substances, forming 20' with hydrogen chloride addition compounds which can be readily split up again. I 5. The process for the manufacture o1. l-chloro- -ethylbenzene, which comprises causing gaseous hydrogen chloride to react on crude solvent naph- :26

tha from coal tar in the presence of'catalytically acting quantities of substances, forming with hydrogen chloride addition compounds which can be readily split up again. i

4 6. The process for themanufacture of l-chloro- 30 ethylbenzene, which comprises causing gaseous hydrogen chloride to react Ion crude solvent, naphtha from coal tar in the presence of catalytically acting quantities of water.

7. The process for the manufacture of l-chloro- 35 ethylbenzene, which comprises causing gaseous hydrogen chloride to react on crude solvent naphtha from coal. tar in the presence of catalytically acting quantities of water at temperatures above 0 C. 2

8. The process forthe-i'nanufacture of l-chloroethylbenzene,- which comprises causing gaseous hydrogen chloride to react on crude solvent naphtha from coal tar in the presence of catalytically acting quantities of water at a temp-, 45

mature from about 5 to about 50 C.

9. Theprocess for themanufacture of l-chloroethylbenzene, which comprises causing gaseous hydrogen chloride to react on crude solvent naphtha from coal tar in the presence of catalyti- 50 cally acting quantities of an organic substance forming with hydrogen chloride an'addition compound which can be readily split up again.

10. The process for the manufacture of l-, chloro-ethylbenzene, which comprises causing 55 gaseous hydrogen chloride to react on crude solvent naphtha' from coal tar in the presence of catalytically a'cting quantities of dimethylaniline.

11. The. process for the manufacture of 1- chloro ethylbenz'ene, which comprises causing 6i) gaseous hydrogen chloride to react on crude solvent naphtha from coal tar in the presence of catalytically acting quantities of dimethylaniline at temperatures above 0 C.

12. The process for the manufacture of 1- 55 chloro-ethylbenzene, which comprises causing gaseous hydrogen chloride to react on crude solvent naphtha from coal tar in the presence of catalytically acting quantities of dimethylaniline at a temperature from about 5 to about 50 C. to

13. The process for the manufacture of lchloro-ethylbenzene, which comprises causing gaseous hydrogen chlorideto reacton crude solvent naphtha from coal tar in the presence of catalytically acting quantities of methyl alcohol. -15

14. The process for the manufacture of 1- ch1oro-ethylbenzene,, which comprises causing gaseous hydrogen chloride to react on crude solvent naphtha from coal tar in the presence of '5 catalytically acting quantities of methyl alcohol at temperatures above 0 C.-

15. The process for ,the manufacture or 1- catalytically acting quantities of methyl alcohol at a temperature from about 5 to about 50 C. HANS 

